A timepiece of this character has been described, for example, in my prior U.S. Pat. Nos. 3,990,226 and 4,308,606. Such timepieces, sometimes referred to as anniversary clocks, generally have an upright clockwork-supporting structure in which the several gear shafts--including the coaxial hour and minute shafts as well as possibly a seconds shaft--of the clockwork are horizontally journaled.
Customers often prefer timepieces of this nature whose supporting structure is apertured so that a user may observe the motion of the clockwork and the interplay of its gears. This is esthetically satisfactory but may cause some inconvenience when the timepiece is to be equipped with ancillary mechanical devices such as the aforementioned torsion pendulum or a linkage designed to trigger the emission of an acoustic signal by a sound generator in the base of the structure upon attainment of a particular clockwork position.